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  Gitee
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<!---->
2021
</a></span></div></div> <div data-v-2d5f533b><main class="page"><div class="page-title" style="display:none;"><h1 class="title">DML语句</h1> <div data-v-3b7f5bdf><i class="iconfont reco-account" data-v-3b7f5bdf><span data-v-3b7f5bdf>pgmanor</span></i> <i class="iconfont reco-date" data-v-3b7f5bdf><span data-v-3b7f5bdf>2021-01-01</span></i> <i class="iconfont reco-eye" data-v-3b7f5bdf><span id="/manor-farm-mysql/zh/guide/essentials/e-03-dml.html" data-flag-title="Your Article Title" class="leancloud-visitors" data-v-3b7f5bdf><a class="leancloud-visitors-count" style="font-size:.9rem;font-weight:normal;color:#999;"></a></span></i> <i class="iconfont reco-tag tags" data-v-3b7f5bdf><span class="tag-item" data-v-3b7f5bdf>dml</span></i></div></div> <div class="theme-reco-content content__default" style="display:none;"><p>本文主要介绍常用的插入、更新、查询、删除数据sql</p> <div id="boxx" data-v-f4ca0dac><div data-v-f4ca0dac><p v-if="true" class="custom-block-title" data-v-f4ca0dac></p> <p v-if="true" data-v-f4ca0dac></p></div></div> <p>以<code>student</code>表为例，演示下如何使用</p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">create</span> <span class="token keyword">table</span> student <span class="token punctuation">(</span>
    id <span class="token keyword">INT</span> <span class="token keyword">AUTO_INCREMENT</span> <span class="token keyword">COMMENT</span> <span class="token string">'id'</span><span class="token punctuation">,</span>
    name <span class="token keyword">VARCHAR</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span> <span class="token keyword">COMMENT</span> <span class="token string">'姓名'</span><span class="token punctuation">,</span>
    age <span class="token keyword">INT</span> <span class="token keyword">COMMENT</span> <span class="token string">'年龄'</span><span class="token punctuation">,</span>
    sex <span class="token keyword">BIT</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)</span> <span class="token keyword">COMMENT</span> <span class="token string">'性别'</span><span class="token punctuation">,</span>
    email <span class="token keyword">VARCHAR</span><span class="token punctuation">(</span><span class="token number">50</span><span class="token punctuation">)</span> <span class="token keyword">COMMENT</span> <span class="token string">'邮件'</span><span class="token punctuation">,</span>
    <span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br></div></div><h2 id="_1-insert">1.insert</h2> <p><strong>INSERT INTO SQL语法：</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> table_name <span class="token punctuation">(</span> field1<span class="token punctuation">,</span> field2<span class="token punctuation">,</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>fieldN <span class="token punctuation">)</span>
                       <span class="token keyword">VALUES</span>
                       <span class="token punctuation">(</span> value1<span class="token punctuation">,</span> value2<span class="token punctuation">,</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>valueN <span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p><strong>student插入数据示例</strong></p> <p>单条插入</p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">insert</span> <span class="token keyword">into</span>
	student <span class="token punctuation">(</span>name<span class="token punctuation">,</span> age<span class="token punctuation">,</span> sex<span class="token punctuation">,</span> email<span class="token punctuation">)</span>
<span class="token keyword">values</span>
	<span class="token punctuation">(</span><span class="token string">'pgmanor'</span><span class="token punctuation">,</span> <span class="token number">18</span><span class="token punctuation">,</span> <span class="token number">1</span><span class="token punctuation">,</span> <span class="token string">'pgmanor@qq.com'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><p>多条插入</p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">insert</span> <span class="token keyword">into</span>
	student <span class="token punctuation">(</span>name<span class="token punctuation">,</span> age<span class="token punctuation">,</span> sex<span class="token punctuation">,</span> email<span class="token punctuation">)</span>
<span class="token keyword">values</span>
	<span class="token punctuation">(</span><span class="token string">'pgmanor_1'</span><span class="token punctuation">,</span> <span class="token number">18</span><span class="token punctuation">,</span> <span class="token number">1</span><span class="token punctuation">,</span> <span class="token string">'pgmanor1@qq.com'</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
	<span class="token punctuation">(</span><span class="token string">'pgmanor_2'</span><span class="token punctuation">,</span> <span class="token number">22</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token string">'pgmanor2@qq.com'</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
	<span class="token punctuation">(</span><span class="token string">'pgmanor_3'</span><span class="token punctuation">,</span> <span class="token number">23</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token string">'pgmanor3@qq.com'</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
	<span class="token punctuation">(</span><span class="token string">'pgmanor_4'</span><span class="token punctuation">,</span> <span class="token number">25</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token string">'pgmanor4@qq.com'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br></div></div><h2 id="_2-update">2.update</h2> <p><strong>更新SQL语法</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">UPDATE</span> table_name <span class="token keyword">SET</span> field1<span class="token operator">=</span>new<span class="token operator">-</span>value1<span class="token punctuation">,</span> field2<span class="token operator">=</span>new<span class="token operator">-</span>value2
<span class="token punctuation">[</span><span class="token keyword">WHERE</span> Clause<span class="token punctuation">]</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><ul><li>多个字段使用<code>,</code>分隔</li> <li>WHERE可以指定条件，满足条件的才更新</li></ul> <p><strong>student更新数据示例</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">update</span> student <span class="token keyword">set</span> age<span class="token operator">=</span>age<span class="token operator">+</span><span class="token number">1</span><span class="token punctuation">,</span> email<span class="token operator">=</span><span class="token string">'pgmanor_new@qq.com'</span> <span class="token keyword">where</span> id <span class="token operator">=</span> <span class="token number">1</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><blockquote><p>更新年龄+1，邮箱更新</p></blockquote> <h2 id="_3-delete">3.delete</h2> <p><strong>删除SQL语法</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">DELETE</span> <span class="token keyword">FROM</span> table_name <span class="token punctuation">[</span><span class="token keyword">WHERE</span> Clause<span class="token punctuation">]</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p><strong>student删除数据示例</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">delete</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span> id <span class="token operator">=</span> <span class="token number">4</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><h2 id="_4-select">4.select</h2> <p><strong>查询SQL语法</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">SELECT</span> column_name<span class="token punctuation">,</span>column_name
<span class="token keyword">FROM</span> table_name
<span class="token punctuation">[</span><span class="token keyword">WHERE</span> Clause<span class="token punctuation">]</span>
<span class="token punctuation">[</span><span class="token keyword">LIMIT</span> N<span class="token punctuation">]</span><span class="token punctuation">[</span> <span class="token keyword">OFFSET</span> M<span class="token punctuation">]</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><ul><li>可以查多个表，或者一个表</li> <li>可以查一个字段或者多个字段</li> <li>可以使用<code>*</code>来代替所有字段，当时开发时候，最好不要用<code>*</code></li> <li>where条件来过滤满足条件的数据</li> <li>limit控制查询数据</li> <li>offset偏移量，用于分页查询</li></ul> <p><strong>student查询数据示例</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token comment">-- 查询所有数据</span>
<span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student<span class="token punctuation">;</span>

<span class="token comment">-- where条件查询</span>
<span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student 
<span class="token keyword">where</span> age <span class="token operator">&lt;</span> <span class="token number">20</span><span class="token punctuation">;</span>

<span class="token comment">-- limit限制条数查询</span>
<span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student 
<span class="token keyword">where</span> age <span class="token operator">&lt;</span> <span class="token number">20</span>
<span class="token keyword">limit</span> <span class="token number">2</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br></div></div><h2 id="_5-where">5.where</h2> <h3 id="_5-1-多条件查询">5-1.多条件查询</h3> <table><thead><tr><th style="text-align:left;">符号</th> <th style="text-align:left;">描述</th> <th style="text-align:left;">实例</th></tr></thead> <tbody><tr><td style="text-align:left;">=</td> <td style="text-align:left;">等号，检测两个值是否相等，如果相等返回true</td> <td style="text-align:left;">(A = B) 返回false。</td></tr> <tr><td style="text-align:left;">&lt;&gt;, !=</td> <td style="text-align:left;">不等于，检测两个值是否相等，如果不相等返回true</td> <td style="text-align:left;">(A != B) 返回 true。</td></tr> <tr><td style="text-align:left;">&gt;</td> <td style="text-align:left;">大于号，检测左边的值是否大于右边的值, 如果左边的值大于右边的值返回true</td> <td style="text-align:left;">(A &gt; B) 返回false。</td></tr> <tr><td style="text-align:left;">&lt;</td> <td style="text-align:left;">小于号，检测左边的值是否小于右边的值, 如果左边的值小于右边的值返回true</td> <td style="text-align:left;">(A &lt; B) 返回 true。</td></tr> <tr><td style="text-align:left;">&gt;=</td> <td style="text-align:left;">大于等于号，检测左边的值是否大于或等于右边的值, 如果左边的值大于或等于右边的值返回true</td> <td style="text-align:left;">(A &gt;= B) 返回false。</td></tr> <tr><td style="text-align:left;">&lt;=</td> <td style="text-align:left;">小于等于号，检测左边的值是否小于或等于右边的值, 如果左边的值小于或等于右边的值返回true</td> <td style="text-align:left;">(A &lt;= B) 返回 true。</td></tr></tbody></table> <p>多个条件之间有and和or的关系</p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span>
	age <span class="token operator">&lt;</span> <span class="token number">20</span>
	<span class="token operator">and</span> sex <span class="token operator">=</span> <span class="token number">1</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><blockquote><p>查询年龄小于20并且sex=1的数据</p></blockquote> <h3 id="_5-2-区分大小写">5-2.区分大小写</h3> <p>myql默认是不区分大小写的，如果需要区分大小写的话，需要使用关键字<code>BINARY</code></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span>
	name<span class="token punctuation">,</span>
	age<span class="token punctuation">,</span>
	sex<span class="token punctuation">,</span>
	email
<span class="token keyword">from</span>
	student
<span class="token keyword">where</span>
	<span class="token keyword">binary</span> name <span class="token operator">=</span> <span class="token string">'pgmanor'</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br></div></div><blockquote><p>将条件修改为大写，查看结果。</p> <ul><li><code>binary</code>: 区分大小写</li> <li>默认：不区分大小写</li></ul></blockquote> <h2 id="_6-like">6. like</h2> <p>like模糊查询，mysql中使用<code>%</code>来代表任何一个字符。</p> <p><strong>语法</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">SELECT</span> field1<span class="token punctuation">,</span> field2<span class="token punctuation">,</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>fieldN 
<span class="token keyword">FROM</span> table_name
<span class="token keyword">WHERE</span> field1 <span class="token operator">LIKE</span> condition1 <span class="token punctuation">[</span><span class="token operator">AND</span> <span class="token punctuation">[</span><span class="token operator">OR</span><span class="token punctuation">]</span><span class="token punctuation">]</span> filed2 <span class="token operator">=</span> <span class="token string">'somevalue'</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p><strong>示例</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span>
	name <span class="token operator">like</span> <span class="token string">'pgmanor%'</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><blockquote><p>查询名称为pgmanor开头的记录，如果查询包含的话，那么可以使用<code>like '%pgmanor%'</code></p> <p>这先不考虑性能问题，只是演示下如何使用like</p></blockquote> <p><strong>结果</strong></p> <table><thead><tr><th>id</th> <th>name</th> <th>age</th> <th>sex</th> <th>email</th></tr></thead> <tbody><tr><td>1</td> <td>pgmanor</td> <td>19</td> <td>1</td> <td>pgmanor_new@qq.com</td></tr> <tr><td>5</td> <td>pgmanor_w</td> <td>15</td> <td>0</td> <td>pgmanor@qq.com</td></tr> <tr><td>6</td> <td>pgmanor_1</td> <td>18</td> <td>1</td> <td>pgmanor1@qq.com</td></tr> <tr><td>7</td> <td>pgmanor_2</td> <td>22</td> <td>0</td> <td>pgmanor2@qq.com</td></tr> <tr><td>8</td> <td>pgmanor_3</td> <td>23</td> <td>0</td> <td>pgmanor3@qq.com</td></tr> <tr><td>9</td> <td>pgmanor_4</td> <td>25</td> <td>0</td> <td>pgmanor4@qq.com</td></tr></tbody></table> <h2 id="_7-null">7. NULL</h2> <p>::: error 警告
当条件为NULL的时候，千万别用 = 和 !=，而用 IS NULL 和 IS NOT NULL
:::</p> <p>我们先插入点NULL的数据，再来演示</p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">insert</span> <span class="token keyword">into</span>
	student <span class="token punctuation">(</span>name<span class="token punctuation">,</span> age<span class="token punctuation">,</span> sex<span class="token punctuation">,</span> email<span class="token punctuation">)</span>
<span class="token keyword">values</span>
	<span class="token punctuation">(</span><span class="token string">'小白'</span><span class="token punctuation">,</span> <span class="token number">22</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token boolean">null</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
	<span class="token punctuation">(</span><span class="token string">'黑客'</span><span class="token punctuation">,</span> <span class="token number">25</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token string">'null'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br></div></div><blockquote><p>注意这的null和字符串'null'的区别</p></blockquote> <h3 id="_7-1-is-null">7-1. IS NULL</h3> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span> email <span class="token operator">is</span> <span class="token boolean">null</span> 
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><p>结果：</p> <table><thead><tr><th>id</th> <th>name</th> <th>age</th> <th>sex</th> <th>email</th></tr></thead> <tbody><tr><td>10</td> <td>小白</td> <td>22</td> <td>0</td> <td></td></tr></tbody></table> <h3 id="_7-2-is-not-null">7-2. IS NOT NULL</h3> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span> email <span class="token operator">is</span> <span class="token operator">not</span> <span class="token boolean">null</span> 
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><p>结果：</p> <table><thead><tr><th>id</th> <th>name</th> <th>age</th> <th>sex</th> <th>email</th></tr></thead> <tbody><tr><td>1</td> <td>pgmanor</td> <td>19</td> <td>1</td> <td>pgmanor_new@qq.com</td></tr> <tr><td>5</td> <td>pgmanor_w</td> <td>23</td> <td>0</td> <td>pgmanor@qq.com</td></tr> <tr><td>6</td> <td>pgmanor_1</td> <td>18</td> <td>1</td> <td>pgmanor1@qq.com</td></tr> <tr><td>7</td> <td>pgmanor_2</td> <td>18</td> <td>0</td> <td>pgmanor2@qq.com</td></tr> <tr><td>8</td> <td>pgmanor_3</td> <td>23</td> <td>0</td> <td>pgmanor3@qq.com</td></tr> <tr><td>9</td> <td>pgmanor_4</td> <td>23</td> <td>0</td> <td>pgmanor4@qq.com</td></tr> <tr><td>11</td> <td>黑客</td> <td>25</td> <td>0</td> <td>null</td></tr></tbody></table> <blockquote><p>黑客的结果也能出来，是因为email为字符串null，是有结果的。</p></blockquote> <h2 id="_8-regular">8.regular</h2> <p>上面我们介绍了like的模糊查询，mysql还支持正则方式</p> <p>常用表达式</p> <table><thead><tr><th style="text-align:left;">模式</th> <th style="text-align:left;">描述</th></tr></thead> <tbody><tr><td style="text-align:left;">^</td> <td style="text-align:left;">匹配输入字符串的开始位置。如果设置了 RegExp 对象的 Multiline 属性，^ 也匹配 '\n' 或 '\r' 之后的位置。</td></tr> <tr><td style="text-align:left;">$</td> <td style="text-align:left;">匹配输入字符串的结束位置。如果设置了RegExp 对象的 Multiline 属性，$ 也匹配 '\n' 或 '\r' 之前的位置。</td></tr> <tr><td style="text-align:left;">.</td> <td style="text-align:left;">匹配除 &quot;\n&quot; 之外的任何单个字符。要匹配包括 '\n' 在内的任何字符，请使用像 '[.\n]' 的模式。</td></tr> <tr><td style="text-align:left;">[...]</td> <td style="text-align:left;">字符集合。匹配所包含的任意一个字符。例如， '[abc]' 可以匹配 &quot;plain&quot; 中的 'a'。</td></tr> <tr><td style="text-align:left;">[^...]</td> <td style="text-align:left;">负值字符集合。匹配未包含的任意字符。例如， '[^abc]' 可以匹配 &quot;plain&quot; 中的'p'。</td></tr> <tr><td style="text-align:left;">p1|p2|p3</td> <td style="text-align:left;">匹配 p1 或 p2 或 p3。例如，'z|food' 能匹配 &quot;z&quot; 或 &quot;food&quot;。'(z|f)ood' 则匹配 &quot;zood&quot; 或 &quot;food&quot;。</td></tr> <tr><td style="text-align:left;">*</td> <td style="text-align:left;">匹配前面的子表达式零次或多次。例如，zo* 能匹配 &quot;z&quot; 以及 &quot;zoo&quot;。* 等价于{0,}。</td></tr> <tr><td style="text-align:left;">+</td> <td style="text-align:left;">匹配前面的子表达式一次或多次。例如，'zo+' 能匹配 &quot;zo&quot; 以及 &quot;zoo&quot;，但不能匹配 &quot;z&quot;。+ 等价于 {1,}。</td></tr> <tr><td style="text-align:left;">{n}</td> <td style="text-align:left;">n 是一个非负整数。匹配确定的 n 次。例如，'o{2}' 不能匹配 &quot;Bob&quot; 中的 'o'，但是能匹配 &quot;food&quot; 中的两个 o。</td></tr> <tr><td style="text-align:left;">{n,m}</td> <td style="text-align:left;">m 和 n 均为非负整数，其中n &lt;= m。最少匹配 n 次且最多匹配 m 次。</td></tr></tbody></table> <p><strong>示例1</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span> name <span class="token operator">regexp</span> <span class="token string">'^pg'</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><blockquote><p>查询以<code>pg</code>开头的数据</p></blockquote> <p><strong>示例2</strong></p> <div class="language-sql line-numbers-mode"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student
<span class="token keyword">where</span> name <span class="token operator">regexp</span> <span class="token string">'pgmanor'</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><blockquote><p>查询包含<code>pgmanor</code>的数据</p></blockquote> <p>更多正则表达方式就不多举例了。</p></div> <footer class="page-edit" style="display:none;"><!----> <div class="last-updated"><span class="prefix">Last Updated: </span> <span class="time">2020-12-20 11:21:37 PM</span></div></footer> <!----> <!----> <!----></main> <!----></div></div></div></div><div class="global-ui"><div class="back-to-ceiling" style="right:1rem;bottom:6rem;width:2.5rem;height:2.5rem;border-radius:.25rem;line-height:2.5rem;display:none;" data-v-c6073ba8 data-v-c6073ba8><svg t="1574745035067" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg" p-id="5404" class="icon" data-v-c6073ba8><path d="M526.60727968 10.90185116a27.675 27.675 0 0 0-29.21455937 0c-131.36607665 82.28402758-218.69155461 228.01873535-218.69155402 394.07834331a462.20625001 462.20625001 0 0 0 5.36959153 69.94390903c1.00431239 6.55289093-0.34802892 13.13561351-3.76865779 18.80351572-32.63518765 54.11355614-51.75690182 118.55860487-51.7569018 187.94566865a371.06718723 371.06718723 0 0 0 11.50484808 91.98906777c6.53300375 25.50556257 41.68394495 28.14064038 52.69160883 4.22606766 17.37162448-37.73630017 42.14135425-72.50938081 72.80769204-103.21549295 2.18761121 3.04276886 4.15646224 6.24463696 6.40373557 9.22774369a1871.4375 1871.4375 0 0 0 140.04691725 5.34970492 1866.36093723 1866.36093723 0 0 0 140.04691723-5.34970492c2.24727335-2.98310674 4.21612437-6.18497483 6.3937923-9.2178004 30.66633723 30.70611158 55.4360664 65.4791928 72.80769147 103.21549355 11.00766384 23.91457269 46.15860503 21.27949489 52.69160879-4.22606768a371.15156223 371.15156223 0 0 0 11.514792-91.99901164c0-69.36717486-19.13165746-133.82216804-51.75690182-187.92578088-3.42062944-5.66790279-4.76302748-12.26056868-3.76865837-18.80351632a462.20625001 462.20625001 0 0 0 5.36959269-69.943909c-0.00994388-166.08943902-87.32547796-311.81420293-218.6915546-394.09823051zM605.93803103 357.87693858a93.93749974 93.93749974 0 1 1-187.89594924 6.1e-7 93.93749974 93.93749974 0 0 1 187.89594924-6.1e-7z" p-id="5405" data-v-c6073ba8></path><path d="M429.50777625 765.63860547C429.50777625 803.39355007 466.44236686 1000.39046097 512.00932183 1000.39046097c45.56695499 0 82.4922232-197.00623328 82.5015456-234.7518555 0-37.75494459-36.9345906-68.35043303-82.4922232-68.34111062-45.57627738-0.00932239-82.52019037 30.59548842-82.51086798 68.34111062z" p-id="5406" data-v-c6073ba8></path></svg></div><!----><!----><APlayer audio="" fixed="true" mini="true" theme="#f9bcdd" loop="loop" order="random" preload="auto" volume="0.1" mutex="true" lrc-type="0" list-folded="true" list-max-height="250" storage-name="vuepress-plugin-meting" id="aplayer-fixed"></APlayer></div></div>
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